1. Field of the Invention
This invention relates to an optical computing element for use in an optical computer which performs optical parallel operation of the multiplex wavelength type.
2. Description of the Prior Art
FIG. 1 is a fundamental schematic diagram illustrating a conventional optical parallel computer as shown, for example, in Oyo Buturi, vol. 54, No. 10 (1985), pp. 1019-1030. The FIG. 1 optical computer is a computer of the so called non von Neumann type in which a central processing unit 16 (hereinafter referred to as CPU) and a memory 17 are interconnected in parallel by a plurality of signal lines through an optical interconnection 8 capable of changing a coupling area. Input of information to the CPU 16 and output from the CPU 16 are channeled through an input output part 18.
Since the CPU 16 and the memory 17 are interconnected in parallel as above mentioned, programs, data items, and the like are written into and read from the memory 17 in parallel relation through individual signal lines.
With such conventional computer of the non von Neumann type, as above mentioned, however, the difficulty is that although there are a multiplicity of signal lines arranged in parallel, one signal line can deal with one signal only, which fact makes it impracticable to perform bulky operation in an efficient manner.
In an attempt to overcome this difficulty there has been proposed an optical computer in which light rays having a plurality of wavelengths are used as computing light rays to enable arithmetic operations to be executed in optical wavelength orders. However, there has been no corresponding development of an element which could control only a particular wavelength component of such computing light rays having a plurality of wavelengths.